efficiently its authority to bring charges and the courts cannot conduct judicial proceedings that this type of violation calls for.”237 163. It has also underscored that “the State’s obligation to carry out investigations with due diligence includes the obligation of all state authorities to collaborate in the gathering of evidence so that the objectives of an investigation may be achieved.”238 Thus, when the investigation is hampered,as was even noticed by a legislative body of the State itself in 1999, it prevents the case from being exhaustively elucidated, because the conduct stemming from the irregularities committed during the combat training exercise was not investigated along with the question of responsibility for the death of Johan Alexis Ortiz, as is explained in detail in the subsequent topic of examination hereinafter. 164. Moreover, the IACHR cannot fail to note that there was an initial official version provided by NG officials to the parents of the alleged victim, which was subsequently discarded in the judicial proceeding, though no clear explanation was provided by the authorities to make such a determination. In the same vein, available evidence –thus far unrefuted by the State- indicates that some military officials linked to the process of military criminal investigation, were promoted from their positions, even though domestic law itself would so prohibit it. 165. The Commission has also factored in that during the time the investigation was under the direction of the military authorities, and according to the case file, the parents were unable to gain access to copies of the proceedings conducted in the case, despite their ongoing efforts and the motions submitted by them for evidence to be collected and tests to be conducted. 166. Therefore, since it was not guaranteed that the proceedings in this essential stage of the case were conducted with adherence to the guarantees of independence and impartiality, the State did not offer to the next-of-kin of Johan Alexis Ortiz Hernandez in this essential stage of the case before the military criminal jurisdiction, an investigation and criminal proceeding by independent and impartial judges,in violation of Article 8 and 25 of the American Convention, in connection with Articles 1 and 2 of said instrument. Due diligence in the investigation and reasonable time period 167. As to the content of the duty to investigate “with due diligence,” the Inter-American Court has stated that this implies that investigations must be conducted using all legal means available and should be oriented toward determination of the truth.239 By the same token, the Court has indicated that the State must adopt such measures as may be necessary to learn the truth about what happened and for those responsible to be punished,240 involving every State institution.241 168. In order to fulfill the obligation to investigate a violation of the right to life, States must act from the initial stages of the proceeding with all due diligence.242 In this regard, the Inter-American Court has 237I/A Court HR., Case of Cantoral Huamaní and García Santa Cruz vs. Peru. Preliminary Objections, Merits, Reparations and Costs. Judgment of July 10, 2007. Series C No. 167. Para. 166. 238I/A Court HR., Case of García Prieto et al vs. El Salvador. Preliminary Objections, Merits, Reparations and Costs. Judgment of November 20, 2007. Series C No. 168. Para. 112. 239 I/A Court HR., Case of García Prieto et al v. El Salvador. Preliminary Objections, Merits, Reparations, and Costs. Judgment of November 20, 2007. Series C No. 168. Par. 101. 240 I/A Court HR, Case of Bulacio. Judgment of September 18, 2003. Series C No. 100. Par. 114; IA Court of HR, Case of the Rochela Massacre. Judgment of May 11, 2007. Series C. No. 163. Par. 146; I/A Court H.R., Case of Miguel Castro Castro Prison. Judgment of November 25, 2006. Series C No. 160. Par. 382. 241 I/A Court H.R., Case of Cantoral Huamaní and García Santa Cruz v. Peru. Preliminary Objections, Merits, Reparations, and Costs. Judgment of July 10, 2007. Series C No. 167. Par. 130; I/A Court H.R., Case of the Pueblo Bello Massacre. Judgment of January 31, 2006. Series C No. 140. Par. 120; and I/A Court H.R., Case of Huilca Tecse. Judgment of March 3, 2005. Series C No. 121, Par. 66. 242 I/A Court H.R., Case of Zambrano Vélez et al. v. Ecuador. Merits, Reparations, and Costs. Judgment of July 4, 2007. Series C No. 166. Par. 121.